What computer application or implementation requires the most lines of code?

For example:

It takes about 20 million lines of code to build a voice/data-processor community (cell phone or landline service area).

IIRC, it took about 40 million lines to build the network that supported one of the earlier extraterrestrial probe projects.

Are there any prospective databases that are too big for our current technology?

How many lines of code do you think it would take to build a matter transporter? ;-0